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Saturday, 30 March 2013

This year I am once again part of the arbiting team at the Doeberl Cup (along with Shaun Press, Charles Zworestine & Lee Forace) & given that the chess content is fairly well-coveted elsewhere on the web, I thought I'd take a look at the other side of things in this blog.
After Friday's events, I have decided to create an Idiot of the Day award, for the silliest thing in the tournament for the day.
Friday had a clear winner, with Anthony Hain deciding (apparently after a dare) to come in a costume of sorts for his round 2 game. Although this might be perfectly fine in a fun or non-rated event, I thought it was totally inappropriate for a prestigious event like the Doeberl Cup!
Saturday's award went to Alana Chibnall, who was playing white against Mark Vucak on board 5. After walking away from the board after making a move, she returned to sit opposite Ilija Ilic who was playing on board 3! To make matters worse, it took Alana close to a minute to realise that she was at the wrong board & spent some time trying to figure out how the position she had left had changed so much after her short stroll around the playing hall! Once she noticed the differences, both in her opponent & the position she was sitting in front of, she sheepishly got out of her seat & returned to board 5! Although Mark @ Ilija both wear glasses & have greyish hair, that is about the extent of the similarities between the two, so well done Alana for winning the award! Incidentally she did go on to beat Mark in the game & now finds herself playing against Ilija on board 1 on the stage!
Close runners up were Anthony Hain, who once again wore his outfit from Friday, but this time did do during the evening blitz tournament & Jose Escribano, who not only left his mobile phone in his pocket (there are rules for players where they are not allowed to have a phone on their person during a game & many leave their phones at the results table), but he left it switched on, so when someone from his local church rang him to wish him a happy Easter & good luck in his chess, his game was brought to an abrupt halt!

At present I'm posting this from my phone (using the Blogger App) as I have been having some computer issues, but hope to update this post (or add another one) with photos in the near future.

Tuesday, 26 March 2013

Round 7 saw Guy West retain his half point lead over Ari Dale, after both players drew their games (against Chris Wallis & Domagoj Dragicevic respectively), however the chasing pack one point behind Guy now has three & could have as many as five players, with a number of postponed games to be played in the coming days. The top board clash between West & Wallis had some interesting moments, with Guy initially employing a 'checkers' pawn structure, with most of his pawns on white squares. After some exchanges, a number of these moved to black squares, before ultimately the players found themselves in a queen & minor piece ending. Early in this ending, it seemed like Guy had the initiative, but once Guy declined a queen trade, Chris' queen invaded Guy's position & in combination with his knight pair created some serious problems for Guy. Ultimately these problems allowed Chris to win a pawn, but his king was exposed & Guy found a perpetual check, so the game was drawn.
Domagoj Dragicevic played a Grunfeld against Ari Dale & Ari seemed to get the better of the opening initially, however Domagoj found a nice tactic to win a pawn, before Ari repeated positions to draw the game. Justin Tan beat Justin Penrose to stay in touch with the leaders, while Laurent Michaille also won his postponed game to join the group of players on 5/7 who are still in with an outside chance to place highly in the tournament.
Most of the other games this round went according to rating, which was a bit of a surprise!
Results for round 7 are on ChessChat.
Below is the game between West & Wallis.

Saturday, 23 March 2013

Round 7 finished with a whimper for me rather than a bang ... I played a horrible game against Eugene Schon (ACF 2234; FIDE 2169), getting a passive position where I had no obvious plan & simply allowed Eugene to outplay me without much of a fight. My opening choice was bad - although there's some theory in the c3 Sicilian, the positions are fairly straightforward & do not need the amount of theoretical knowledge that a Dragon or Najdorf might require. Of course by avoiding the main lines with an early d4, I found myself in a passive position with pieces that were practically useless. It didn't help that I didn't consider a number of moves that Eugene made, meaning I wasn't really at my best. Anyway, Eugene played well in the game & deserved the win. The final cross table is something of a description of how players fared against me - those that beat me (Hacche & Schon) finished =1st, those that were higher rated than me & lost to me (Li & Zelesco) finished =3rd, while those lower rated than me that I beat (Lin, Ni & Foo) finished below me.
As far as my next tournament is concerned, I'm not sure what I'll be playing, although I will definitely be playing in the Billanook Classic, although that is an allegro series rather than 'classic' time limit games. Perhaps the Victorian Open or something like that, but I suppose I'll decide closer to the event.

Thursday, 21 March 2013

With the AFL season about to start, with Adelaide v Essendon on Friday night, I thought it was about time I posted what at the moment is my starting squad in the AFL Dream Team competition. The real trick to this game is to find those players that will make you money quickly by over-performing from their starting value, combined with having players who will score the highest in each position throughout the year. As the season progresses, you trade in these over-performers for the high scorers, with the aim being that by the end of the season you will have the best possible team. Of course the related trick is to make the right trades at the right time, which is where things get complicated, however the revised rules regarding trades (you now get up to two trades every week of the season, rather than having a limit on the total number of trades made during the season) should make trading even more important. Add to that the revised team structure, with one less defender & forward, but two extra midfielders, and there should be some very high scores posted, so one would need to be on the pace early to be in contention for the overall prize at the end of the season.
With that as a way of introduction, here is my current AFL Dream Team

You can also join my league & play against me throughout the season. The code to register is 795381.

In terms of the team, it looks like this year there is a real shortage of good rookie forwards, while there are a number of very promising rookie midfielders & some good defenders as well. I think this factor determines the basic structure of the team - starting with 6 'known' forwards, while putting most of the rookies in the team on the bench or in the midfield.
Most of the premium selections are fairly obvious - Goddard & Gibbs should be two of the highest scoring defenders & have shown good scoring potential during the NAB Cup. Ablett & Pendlebury are stars of the competition (and Pendlebury is even a little under-priced after his leg injury last year), while Maric established himself as one of the best rucks going around. I've stacked the forwards, with Franklin, Cox (now a Forward/Ruck), Bartel, Zorko & Rockliff all likely to be in the top 10 scoring forwards by season's end.
There are a few picks which are aimed at getting players who I think will become premium scorers (even if their initial starting price might suggest otherwise), as well as a few underpriced players who will hopefully score much better than they have in previous years. These players are Hartlett & Hibberd in defense, Fyfe & Moloney in the midfield, Bellchambers in the Ruck & Karnezis in the forwards. I's generally very happy with these selections & am confident that most of them will improve their scoring during the year.
The other part of Dream Team that requires a bit of good selection, combined with good fortune is the rookies & these are still not completely locked in for me at this stage, with the all important round 1 selection being a big factor in my decision. Goodes, O'Meara & Wines have stood out in the pre-season & look like they will be definite starters for their respective teams in round 1. In terms of the other rookie defenders, Vlastuin has probably been the best from a points perspective, but there is talk about him being 'vested' & either starting as the sub, or finishing as the sub, giving him only limited game time (which obviously limits scoring potential), while Terlich is likely to play, but does not seem to be as high scoring as Vlastuin. Stevenson is an interesting case, as there are a number of young defenders at Port Adelaide who are effectively fighting for the same positions - Pittard, Colquhoun & Heath being the others - though Pittard & Stevenson seem the most likely to get round 1 selections based on NAB Cup form. In terms of forwards, there's a real issue, with Macaffer being the only standout selection & I really only expect 40-70 scores from him, rather than the potential 100s that you might see from some rookie mids during the year. Spangher is in my squad at present as he seems to be vying for the backline spot at Hawthorn created by Suckling's season-ending knee injury, though that will be one place that I'm not locking in until I see the teams next weekend! In the rucks, Currie looked impressive all pre-season until the final game & the North Melbourne coach has said he doesn't want to start with two ruckmen, so there's a chance he might not be selected in round 1. Daw is another possibility if I need a replacement, although he also lacks job security. Blicavs has come from nowhere & has been the first player to be re-classified (he's now a Mid/Ruck, rather than just a Mid) before the season has started. From all reports he has played well in the pre-season & his fantasy scoring has been reasonable, but he potentially has more job security, at least in the short term, with the injuries to the usual Geelong rucks. The remaining rookie mids are a potential goldmine or headache! Whitfield looks like a great player & has backed it up with great fantasy numbers, but the 'rotation policy' at GWS means that he might not play for a lot of the season, which would be frustrating. Mitchell has looked promising, although like Currie, he also had a quiet final NAB Cup game & is still on the Port Adelaide rookie list, which would mean that he can't play yet. Of course that could change, with Port having a player on their long term injury list, so their is a spot available for him to take, but the longer this decision takes (in spite of all the internet talk that he is 'guaranteed' the place), the more hesitant I am about including him in my team. Brad Crouch was supposed to be one of the 'must have' rookies this year, being selected by Adelaide in 2011 when he was too young to play AFL games, so he has had two pre-seasons & has looked promising in the NAB Cup. Of course with Adelaide having a quality midfield, with the likes of Thompson, Dangerfield, Sloane, Van Berlo, Vince, etc there was always a rick that there might not be a place for him in the team & the round 1 selections seem to have confirmed that, with no Crouch in sight in the team lists. This has me strongly considering swapping him for Kommer from Essendon, who has been named & who had a decent, though far from outstanding, pre-season. Viney is my final rookie midfielder & he has been another 'must have' since the start of the year, however he only played one pre-season game due to a 'minor' injury & his average scoring in that game did not scream 'must have' to me. Of course Melbourne also have a strange history with some of their recent rookie recruits (Watts, Magner, Couch), so although he is apparently a definite starter, I'm still not entirely convinced.
In terms of trading, my main emphasis early on in the season will be getting premium mids into my team - the likes of Swan, Dangerfield, Delidio, Watson & the like. Of course if someone else turns up in another position, they may also become a priority, but upgrading the mids will be the main focus of my early trades.
Hopefully it turns out well & I'll keep posting the occasional update here, but join my league if you really want to see how things go!

Round 6 saw the first 'crack' in Guy West's armour, with Justin Tan holding him to a draw. Or perhaps it was the other way around, with Justin having the better of the endgame & being a pawn ahead when the draw was agreed. Either way, it means that Guy now only has a half-point lead over Ari Dale, following Ari's win over Dusan Stojic in the battle of the 'contenders'. Chris Wallis & Domagoj Dragicevic both won their games to remain a further half point behind & it would be tough to see the tournament winner coming from outside this group of four at this stage of the event.
In other results, Paul Kovacevic drew with David Beaumont, while the big draw of the round was Finley Dale drawing with IM Mirko Rujevic. Jason Chew defeated Richard Voon in another good result for the juniors in the event.
Results for round 6 are on ChessChat.
Below is the top board clash between Guy West & Justin Tan.

Tuesday, 19 March 2013

The final Northern Star Chess Sunday squad session for the term was another enjoyable day at Eltham High.
This week we started with another puzzle, which took a while for the kids to figure out as the solution is somewhat counter-intuitive.

The importance in this position is to make forcing moves, as any non-forcing move allows black to play Rxh6+ followed by c1=Q+, which allows black to get at least a draw, if not more.
The solution is 1.d8=N+ Kf6 2.g8=N+, with a technical win after 2...Rxg8 3.Kxg8 (albeit requiring knowledge of how to checkmate with bishop, knight & king against a lone king), while 2...Kf5 allows 3.Ne7+ followed by capturing the rook, with another technically winning endgame (albeit a little easier with the extra knight).
I also explained to the students how rare such an ending is in tournament chess - I have been playing tournaments for around 20 years & have only had this ending occur once (and that was only last year in the Sydney International)!
For the sake of completeness, here is the game in question, which I played against Emma Guo.

This week's board, with the outline for the day, as well as the final position (actually a few moves after the final position) in the game Georgiev-Rogers, which is one of the best finishes to a game by Australian GM Ian Rogers, who was the 'feature player' of the day.

Ian Rogers was the first Australian born & raised player to become a Grandmaster (Walter Browne was one example of an Australian-born player who became a Grandmaster, but he moved to America at a young age, although he did represent Australia at two Olympiads in the early 1970s). Ian's style was described in similar terms by Doug Hamilton & Guy West in Australian Chess at the Top as a very pragmatic, tactical style. Ian's opening preparation & knowledge, particularly in obscure openings, was also described as particularly strong & I know from experience that Ian can definitely finish an opponent off quickly if they go wrong in the opening.
The first game we looked at was a Rogers' brilliancy from the 1992 Chess Olympiad, against Brazilian GM Gilberto Milos, which highlighted Ian's tactical ability, with both the piece sacrifice 26.Bxc6+ & the final combination beginning with 31.Rdc3 being excellent examples of Rogers in full flight!

The group also looked at the finish to the game Georgiev-Rogers from the Biel Interzonal of 1993, which was another example of a sparkling tactical finish!

Below is the game in its entirety

After looking at these games of Rogers, the group played games which I will analyse later, although from a quick look at some of them, all players need to work on their defensive side of their games!
The final session of the day looked at another example of bishops v knights, this time form the game O'Kelly-Najdorf from the 1950 Chess Olympiad, starting from the following position:

Believe it or not, this position is all about bishops v knights, with the critical pieces being the black knight on c5 & the white bishop on g2, with the resulting position being advantageous to black, as the g2 bishop is hemmed in by its own pawns, while the knight's movement is not restricted in any way. The finish of the game is a very good demonstration of the power of a good knight & the problem of a bad bishop.

I finished off the session with some checkmating patterns, with a somewhat self-indulgent method of looking at checkmates from my own games, with the conclusion to three games being shown to the group.

The first position is from a 2010 game against Ari Dale, where I managed to win as white in the above position, although my method was not the most economical.
The game finished 38. Bd4+ Ka6 39. Qc5 c3+ 40. Kxc3 Qc6 41. b5+ & Ari resigned when faced with various unstoppable checkmate threats (41... Qxb5 42.Qa6# or 41... Ka5 42. bxc6+ Ka4 43. Qb4# or 41... Ka5 42. bxc6+ Ka6 43. Qb6#)
However if I play things in a different move order, the finish is quicker: 38. Bd4+ Ka6 39. b5+! with the following options:
39... Ka5 40. Qb4#
39... Kxb5 40. Qc5+ Ka4 41. Qb4#
39... Kxb5 40. Qc5+ Ka6 41. Qb6#

The second position is from a 2011 game against Kevin Brown, where I won as black with a nice tactic to finish the game (although I am already doing well in the position).
The game ended with Kevin resigning after 39... Rd1, which is a nice deflection tactic, as the queen on c1 is tied to the defense of the b2 square. The kids needed to find not only the winning move, but the variations to checkmate, which run as follows:
40. Qxd1 Qb2#
40. Qa3 Ra1+ 41. Kxa1 Qxa3+ 42. Kb1 Qb2#
40. Qb1 Qa4#
40. Qa1 Qa4#
Any other move allows an eventual Qb2#

The final position is from a 2012 game of mine where I was white against Gavin Marner. It is also one of the many checkmate problems in Gary Lane's recently published book Gary Lane's Chess Puzzles.
The game ended with the spectacular 32. Qxh7+ Kxh7 33. Rh1+ Kg7 34. Bh6+ Kf6 35. Ng8#
The alternative defensive option 34... Kh8 provides no relief for the king due to 35. Bf8#
The difficulty with this position is that if white doesn't find a way to win, black has a number of threats to go with the extra two pawns in the position, so accurate calculation & self-belief are needed to find a way to win the game.

Saturday, 16 March 2013

After the week off for the Labour Day long weekend (and Ballarat weekender, although I didn't attend it this year) the Autumn Cup resumed at Box Hill on Friday night. Although I was a point clear of the field at the start of the round, I was not going to get an easy game & played recently-titled FM David Hacche (ACF 2086; FIDE 2071). I wasn't quite sure what to play before the game & ended up playing a 'Sniper', which I was unsure about against David, as I know he has played the opening himself from time to time, so the usual advantage of being in a position I would be familiar with, but the opponent less so would not really apply in such a case. The game itself turned into a strange Benko-like position where I felt comfortable with my position, even though the various engines may have not agreed with this assessment of the position. Everything seemed to be progressing fine until move 14, when I played the mistimed Ne5, overlooking David's reply 15.b4! which definitely turned the game in his favour. I thought the tactical solution I tried in the game was my only chance, but it left me with serious weaknesses on the kingside & I failed to find the best defense, which was a bit disappointing & ultimately lost the game without much of a fight.
The loss has left me in a five-way tie for the lead, and I have a feeling that I will get the toughest pairing, with it likely that I will be playing second seed Eugene Schon, as I am the third ranked of five players tied for the lead. However I have not checked the previous rounds to see if there are any pairings that are not possible that might change the pairing I think I might be getting. At least it should make for an interesting final round!

Friday, 8 March 2013

Round 5 of the Melbourne Chess Club Championships looked like it was fairly routine going by the results of the top boards, but this was in fact far from the truth! The apparent board 1 mismatch between Phillip Drew & IM Guy West turned out to be a very close game & was one of the last to finish. Guy played the Benko Gambit & Phillip took the offered pawn & managed to neutralise much of Guy's queenside play that is typical in the Benko Gambit. Ultimately the game went into a rook ending, where Guy won back his gambit pawn, but with 4 pawns each (none of them passed), the game appeared to be headed towards a draw. After more exchanges, the players ended up in a pawn ending, with Guy having 2 pawns to Phillip's one, but with Guy's king being away from the action (the pawns were on the d & e files) on the h-file. Unfortunately for Phillip, he played one quick, careless move & discovered to his horror that after his Kf5 & Guy's reply Kg3 that his position was in fact lost! If Phillip had played the correct Kf4, Guy would be unable to make progress & the game would have finished in the draw that it looked headed towards for so long.
In other top board results, Domagoj Dragicevic & Chris Wallis played a fighting draw, while David Beaumont gave up a pawn on the white side of a Grunfeld against Dusan Stojic & missed a devious trick Dusan set when David tried to recover the pawn, which left Dusan a piece ahead. Ari Dale was very lucky to win against Laurent Michaille after sacrificing a rook for a speculative kingside attack. Laurent appeared to have everything under control until he played the natural looking 28...Rc8, rather than the tactical 28...Qa4 which seemed to retain the advantage in the position. Laurent then further compounded his problems by playing 29...Qxd5, which let Ari have the better of the position. However Ari then took the wrong pawn, playing 32.fxg6 (rather than the computer preference 32.gxf6), which allowed Laurent a final chance to draw the game. Unfortunately for Laurent, he missed the key move 34...Re1, which threatens to promote the d-pawn, as well as Nc1+, with a perpetual check. Instead, Laurent played 34...Ng1 & Ari found the tactic 36.Qxe7 to finish the game off. Sylvester Urban made the strategic mistake of playing a Sicilian Dragon against Justin Tan, and played down the same line that Justin had played previously against Brodie McClymont. To make matters worse, the record for black in that line is not exactly inspiring, with 12 games following the game to move 21 there were nine wins for white & three draws (no black wins). Justin showed why the line isn't favourable for black once again & won a nice game to stay in touch with the leaders.
Other results that went against rating saw Felix Wyss, Finley Dale & Tanya Kolak defeat higher rated opponents. With Guy leading the tournament by a clear point, he is the obvious favourite, but there are still plenty of strong players just behind him, so the battle for the title is still very much alive!

Tuesday, 5 March 2013

Another Sunday saw another fun session with the Northern Star Chess Squad at Eltham High! Now that we have some 'regulars', the group is able to get through even more material ... and some fascinating chess!
This week we started with the solution to last week's mystery puzzle ... White has a Queen, Knight & King against Black's King & all you know about the position is that white plays Nc6-d8#. The challenge is to correctly locate all the pieces on the board to make this a reality.

The correct solution has a white queen on g5, knight on c6 (obviously) & king on c7, while the black king is on e6, so Nd8# is possible. The important aspect that stands out with this puzzle is that all the white pieces are helping control at least 2 squares that the black king could potentially escape to, yet there is no 'doubling up', with each square around the black king defended only once, making for the most economical use of pieces!

This week's board, with the daily outline & the first position from the Creating Checkmates section. The group were enthralled by Shirov's games, so we didn't have time to look at another bishops v knights position that I had hoped to look at ... though it will most likely fit into the final session for the term (in a fortnight as next weekend is a long weekend).

After the puzzle, we looked at Spanish (formerly Latvian) Grandmaster Alexei Shirov, who plays a fascinating attacking style of chess that I love to watch! Shirov's love of complicated positions, particularly from the Botvinnik Semi-Slav, make for exciting chess, although playing such 'knife edge' chess does have its risks & this is one of the reasons Shirov has not been able to stay in the upper echelon of players in the world for an extended period of time (although in recent times he has been a fixture in the top 50, I'm talking about being in the top 3 or 4 players in the world).
The first game we looked at was a fascinating game between Vladimir Kramnik & Shirov, where Shirov appeared to be in trouble for much of the game. However it is a great example of Shirov's fighting ability & willingness to play chess on the edge of disaster, with the amazing 31...Re4!! being a fantastic move which turns the tables on Kramnik & is the start of the end after Kramnik goes astray.

The group were amazed by the way Shirov played the end of this game & were move shocked when I showed them the famous finish his game against Topalov from Linares 1998, which has been called the Greatest Move of All Time by John Emms, as well as a number of others.

Here is the game in its entirety - not the most interesting game, but the finish is definitely something to see!

After looking at Shirov, the students played some games, which I will examine later in the week.
To conclude the group for this week, we looked at constructing checkmating positions with pieces, where the pieces were set up without the black king & the students had to locate the correct square (or squares) where the black king could be placed so that the position was checkmate.
Here is an example of the type of positions we looked at:
The next (and final session for the term) is in two weeks time & hopefully the group will continue to grow, particularly with a big term 2 planned!

Friday, 1 March 2013

It took until round 5 of the Box Hill Autumn Cup, but I finally managed to play a decent game! This time I was white against another junior, Karl Zelesco (ACF 2187; FIDE 2147) & ended up playing a 'White Lion', or the aggressive Philidor Attack, as I prefer to call it. It is an opening I was shown many years ago by Ronald Scott, who seemed to play it constantly online & managed to rack up win after win with it! It is essentially a system you can play against most openings & I decided to use it against Karl's Caro Kann, which in itself was something of a surprise, as I was expecting 1.e4 e5 & was hoping for the white side of some 'Spanish Torture', as most of Karl's recent games I had seen had him playing 1...e5. Of course I had played against Karl's Caro Kann in the past, when I wheeled out a BDG, but decided that such a blatantly unsound opening might be giving him a bit too much of a head start, particularly now that he has established himself as a 2000+ player, so opted for something more 'normal'.
The opening is interesting, as the idea of 2.d3 & 3.Nd2 is to remain flexible, while keeping queens on the board. I have the option of heading into a King's Indian Attack with Nf3, g3, Bg2, 0-0, etc, or to play in Philidor style with Be2, c3, Qc2, Nf3, etc. I decided on the latter, as the attacking ideas for white are fairly straightforward & its surprisingly easy for black to go wrong early on in the game.
Karl's first problematic move was 6...0-0, as it gives me a target early on in the game & my position is flexible enough that I still have options involving 0-0, 0-0-0, or even leaving the king in the centre, which can lead to very different types of positions. The difficulties were compounded when Karl played 9...h6, creating a 'hook' for a pawn storm, which will allow white a fairly simple way to open a file on the king-side. This inaccuracy was compounded by the next few moves, 10...Kh7 & 11...Ne8, after which I think I have a fairly solid edge. I think the position after move 14 really highlights the problems for black when you look at things in terms of general principles - although white's king is still in the middle, all four minor pieces are developed on good squares, while the semi-open g-file is an obvious place to put a rook, with only the a1 rook not in a useful attacking position; black on the other hand still has a knight on b8 & rook on a8, while the e8 knight doesn't have too many potential squares to head to. Although black may notionally have more central control with pawns on e5 & d5, the lack of development & somewhat 'airy' king are very problematic & mean that black will have a hard time holding the position.
In terms of the position itself, Karl seems to have missed an opportunity with 18...d4, which would have created a few problems for me that are awkward to deal with & my engine in fact prefers 18.d4 to the Qd1 I chose to play in the game. 18...Qf7 however was quite a serious error from Karl, although the position is already getting difficult to defend at this early stage of the game. After 19.Ngf5! white is clearly better, with multiple threats, including Nh6 & Nxg6. Once Karl allowed 20.Nh6, winning an exchange, I think the game then turns into a more technical phase - yes, there may be mating possibilities (which I may or may not see), but if nothing else I have a material advantage for the endgame.
I really liked the move 22.Bh5, although I don't think I reacted as best I could after Karl's 22...g5 & I spent quite a bit of time looking at 23.Bg6+ (the idea being to clear h5 for the queen), as well as 23.Nf5 before finally deciding on 23.Bg4. Although Bg4 is by no means a bad move, my computer prefers the immediate 23.Nf5, giving me a +6 advantage (as opposed to 23.Bg4, which is evaluates as roughly +4.5). I was somewhat frustrated by the position after 26...Nh7, as I could not see an immediate checkmate & spent some more time trying to make 27.g6 work (my computer thinks it is best, with a +12 evaluation!), although I was not unhappy with my choice of 27.b3, as it essentially killed off any counterplay by black (there were a few lines where I was concerned about Qxa2 & Qa1+ ideas) & retained the attacking chances on the king-side. The main point is seen after 29.Nh6, when black is again faced with a difficult decision, with g6 being a serious threat, as well as having to deal with Nxg8 & the potential issues with the rooks on the g & h files. The finish with 33.Rxh7 seemed fairly logical, although there was apparently a few quicker wins with 33.Ne7 or 33.f3.
The win leaves me a full point clear of the field, although there are quite a few players on 4/5. In terms of likely opponents, I think I might get David Hacche (I had overlooked pairing rule B5 in my previous post & doubt I'll play Eugene in round 6 due to rule B6), although with so many players in the 4/5 score group there are a number of possible opponents for me.